Five decades ago planners envisioned BART trains running from San Jose to San Francisco. Here is the history behind why that hasn’t happened.

The Early years

1953-55: All nine Bay Area counties are involved in the planning, but an early sign of trouble comes in Santa Clara County, where elected officials and community leaders are upset that the first stage of construction would bring trains only to Palo Alto.

1961: San Mateo County supervisors vote to leave BART, saying their voters would be paying taxes to carry mainly Santa Clara County residents. Real estate agent David Bohannon influenced the supervisors to drop out, fearing it would affect planned development along I-280.

The 1990s

1992: Santa Clara County passes a half-cent sales tax to extend light rail to Fremont. The tax is later ruled invalid.

1996: Santa Clara County passes another half-cent sales tax to pay for commuter train service from the Union City BART station into the county. Plans are later canceled.

1999: Meetings begin between San Jose Mayor Ron Gonzales and East Bay officials to explore extending BART to San Jose.

2000 to now

2000: Gov. Gray Davis earmarks $760 million for a BART extension to San Jose. Polls show very high support for the extension. But county supervisors block a tax plan that would need a majority vote. The VTA approves a 30-year tax for the November ballot, saying a new tax would be needed by 2014 to pay for operating costs. It gets a 71 percent vote.

2002: The dot-com recession slams Silicon Valley. The Valley Transportation Aauthority says it needs a new sales tax by 2006 to build BART and pay for transit operations.